The inevitable conclusion is that every effort should be made to guard the precious level of organic matter that exists. The purchase of feedstuffs and the return of manure can help increase farm fertility. Organic matter build-up may be more rapid when manure is applied to bluegrass sod if nothing is removed. Although desirable, this procedure is too expensive to be practical. In any event, a soil having an organic matter level of 5.0% represents a formation many, many years in the making.